Studies by the U.S. Environmental Protection Agency (EPA) have demonstrated that stormwater runoff is one of the most significant sources of water pollution. Rain or snow melt can pick up pollutants and wash them into the town’s drainage system, and this polluted stormwater runoff can be discharged into local rivers and streams without adequate treatment.

Common pollutants include motor oils, fuels, greases and metals from vehicles; pesticides and lawn fertilizers; construction dust and sediment; and litter such as cigarette butts, paper wrappers and plastic bottles.

In combination, these pollutants can clog waterways, degrade animal habitat, and contaminate drinking water. The increased volume and rate of flow can contribute to increased flooding, causing erosion of streambeds and siltation of waterways, and decreasing the amount of water recharged to aquifers. Why Stormwater Matters Presentation (PDF)

Stormwater is managed through a combination of engineering, construction, maintenance and public outreach to address the quality and quantity of runoff. Much of the stormwater that flows onto Weston’s roads is directed to ponds, wetlands, and streams through a Municipal Separate Storm Sewer System (MS4).

The town is authorized to discharge stormwater through the Phase II National Pollutant Discharge Elimination System (NPDES) general permit for small MS4s.

Stormwater management must be addressed when some activities are proposed on a certain residential, municipal, or commercial properties that seek a permit from the Conservation Commission or Planning Board.

The Town’s existing stormwater by-law provides the ability for the Town to ensure that construction activities do not increase stormwater runoff onto town streets only. Currently however, a property owner can clear-cut their property, bring in truck-loads of fill, change drainage characteristics, and pave their backyard with almost no consideration for stormwater impacts on neighbors or nearby wetlands. The Town has limited means to get involved and in order to seek relief; the aggrieved abutter would need to file a private nuisance suit in court.